Dynamic changes in the dimensions of the lumbar spinal canal: An experimental study in vitro

✍ Scribed by Dr. Nils Schönström; Sven Lindahl; Jan Willén; Tommy Hansson

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 551 KB
• Volume: 7
• Category: Article
• ISSN: 0736-0266
• DOI: 10.1002/jor.1100070116

✦ Synopsis

The variation in the dimensions of the lumbar spinal canal under both flexion-extension and axial compression-distraction was studied using computerized tomography (CT) scans in human cadaver lumbar spine specimens. In 3-mm-thick CT slices through the disk at L,-L,, the cross-sectional area of the spinal canal was reduced by around 40 mm2, corresponding to a 16% reduction of the initial area when the lumbar spines were moved both from flexion to extension and from distraction to compression. A corresponding reduction in the midsagittal diameter of the canal of 2 mm was found. During these motions, the ligamentum flavum did not appear to be a significant factor for the dynamic changes affecting the dimensions of the canal. This held true even after the disk had been excised in order to produce a total collapse of the disk space.